The day before seving, prepare the pizza dough. While the dough is rising, heat 3 tablespoons of the olive oil in a large saute pan on medium-high heat until sizzlling, about 2 minutes. Add the onion and garlic, reduce the heat to medium and saute for 1 minute. Add the mushrooms, basil, oregano, 1/2 teaspoon of the salt, the pepper and red pepper flakes. Cook for 10 minutes, stirring occasionally, until the onions and mushrooms are limp and dry. Take off the heat and stir in the spinach and ricotta. Set aside.

Cut the eggplant lengthwise into 1/4 inch slices. Sprinkle the slices with the remaining 1/2 teaspoon fo the salt and place them in a colander to drain for 20 minutes. Pat the slices dry with a paper towel. Line the bottom of a baking sheet with parchment paper. Brush the eggplant slices with the remaining 1/4 cup olive oil and bake in a 425 F preheated oven for 10 minutes on each side. Remove from the oven and set aside.

Preheat the oven to 400 F. Roll out 3/4 of the pizza dough to a 15 inch circle, approximately 1/2 inch thick. Place the dough into a 9 x 3 inch springform pan. You should have a 1 inch overhang all around the pan. Layer 1/2 of each ingredient in the pan in the following order: ham, spinach mixture, peppers, eggplant, cheese and olives. Repeat with the remaining ingredients.

Roll out the remaining dough into a circle to fit the top of the Torta Rustica. Lay it over the top and fold up the overhanging dough, crimping them together to seal the edges. Make 4 small slits in the top to let steam escape and brush with the beaten egg.

Place the Torta Rustica in the preheated oven and bake for 1 hour until the internal temperature in the middle reaches 120 F. About 20 minutes into the baking, cover the Torta Rustica with a tent of aluminum foil to keep the top from getting too brown. Remove from the oven, let cool for 1 hour, then cover with plastic wrap and refrigerate overnight.

Remove the Torta Rustica from the refrigerator about 1 hour before serving to bring to room temperature. Cut it into wedges and serve.

Chef's Tip:

If you prefer your Torta Rustica warmed, place the slices on a baking sheet. Warm in a preheated 400 F oven for 5-8 minutes. Unless you enjoy crisp, browned edges, as I do, loosley cover it with a piece of foil.